Superconducting quantum interference phenomenon in Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$ single crystals

Abstract

The operational dc-SQUID based on intrinsic Josephson junctions in Bi${}_2$Sr${}_2$CaCu2O${}_{8+\delta }$ high-$T_c$ superconductor is fabricated and studied. The novel in-plane loop layout and the developed in-situ endpoint detection method allowed an accurate control of the number of junctions in the SQUID. A clear periodic modulation of the superconducting current as a function of magnetic flux through the SQUID loop is observed. This is an unambiguous evidence for the quantum interference phenomenon in Bi${}_2$Sr${}_2$CaCu2O${}_{8+\delta }$ single crystals.

3 pages, 3 figures